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Virulence Dec 2021Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent in the human population. These viruses cause lifelong infections by establishing latency in... (Review)
Review
Herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent in the human population. These viruses cause lifelong infections by establishing latency in neurons and undergo sporadic reactivations that promote recurrent disease and new infections. The success of HSVs in persisting in infected individuals is likely due to their multiple molecular determinants involved in escaping the host antiviral and immune responses. Importantly, HSVs infect and negatively modulate the function of dendritic cells (DCs), key immune cells that are involved in establishing effective and balanced immunity against viruses. Here, we review and discuss several molecular and cellular processes modulated by HSVs in DCs, such as autophagy, apoptosis, and the unfolded protein response. Given the central role of DCs in establishing optimal antiviral immunity, particular emphasis should be given to the outcome of the interactions occurring between HSVs and DCs.
Topics: Antiviral Agents; Dendritic Cells; Herpes Simplex; Herpesvirus 1, Human; Humans
PubMed: 34895058
DOI: 10.1080/21505594.2021.1980990 -
Biomedicine & Pharmacotherapy =... Dec 2022The world is faces a significant global health challenge in the form of viral infections, particularly the emergence of viral strains that are resistant to effective... (Review)
Review
The world is faces a significant global health challenge in the form of viral infections, particularly the emergence of viral strains that are resistant to effective antiviral therapies. This underscores the urgent need for the development of effective and safe antiviral agents. Nanoscale materials are now being used as novel antiviral agents. Cerium nanoparticles have unique chemical and physical properties that make them particularly promising for viral infections. These particles reduce inflammation and the autoimmune response. Cerium nanoparticles, in addition to their antiviral properties, have many other advantages that are highly sought after for various aspects of biomedical applications. This review focuses on the various properties of cerium nanoparticles as a novel agent against viral infections.
Topics: Humans; Cerium; Nanoparticles; Antioxidants; Virus Diseases; Antiviral Agents
PubMed: 36257210
DOI: 10.1016/j.biopha.2022.113868 -
Life Sciences Jan 2021Outbreaks and the rapid transmission of viruses, such as coronaviruses and influenza viruses, are serious threats to human health. A major challenge in combating... (Review)
Review
Outbreaks and the rapid transmission of viruses, such as coronaviruses and influenza viruses, are serious threats to human health. A major challenge in combating infectious diseases caused by viruses is the lack of effective methods for prevention and treatment. Nanotechnology has provided a basis for the development of novel antiviral strategies. Owing to their large modifiable surfaces that can be functionalized with multiple molecules to realize sophisticated designs, nanomaterials have been developed as nanodrugs, nanocarriers, and nano-based vaccines to effectively induce sufficient immunologic memory. From this perspective, we introduce various nanomaterials with diverse antiviral mechanisms and summarize how nano-based antiviral agents protect against viral infection at the molecular, cellular, and organismal levels. We summarize the applications of nanomaterials for defense against emerging viruses by trapping and inactivating viruses and inhibiting viral entry and replication. We also discuss recent progress in nano-based vaccines with a focus on the mechanisms by which nanomaterials contribute to immunogenicity. We further describe how nanotechnology may improve vaccine efficacy by delivering large amounts of antigens to target immune cells and enhancing the immune response by mimicking viral structures and activating dendritic cells. Finally, we provide an overview of future prospects for nano-based antiviral agents and vaccines.
Topics: Antiviral Agents; Humans; Nanocapsules; Nanotechnology; Viral Vaccines; Virus Diseases
PubMed: 33189824
DOI: 10.1016/j.lfs.2020.118761 -
Expert Review of Respiratory Medicine Aug 2021Therapy of coronavirus disease 2019 (COVID-19) involves evolving algorithms that include drugs aimed at reducing disease progression by counteracting two different, but...
INTRODUCTION
Therapy of coronavirus disease 2019 (COVID-19) involves evolving algorithms that include drugs aimed at reducing disease progression by counteracting two different, but intertwined processes: () the damage caused by the virus (with antivirals); () the damage caused by a dysregulated host response (with immunomodulatory agents).
AREAS COVERED
Herein, we discuss the available evidence on the efficacy and safety of antiviral agents employed over the past months for the treatment of COVID-19, and the reasons to be considered for antiviral selection.
EXPERT OPINION
The available evidence from randomized controlled trials (RCT) currently discourages the use of lopinavir/ritonavir, hydroxychloroquine, and interferons, which did not show improved efficacy compared to standard care or placebo. Regarding remdesivir, the current body of evidence may conditionally support its use in COVID-19 patients requiring oxygen supplementation but still not requiring invasive mechanical ventilation. Finally, neutralizing monoclonal antibodies have been proven efficacious in reducing the risk of severe disease development if administered early in the course of the disease to patients at risk of progression. The results of the ongoing RCT will certainly be crucial to further improve our understanding of the optimal place in therapy of antiviral agents for COVID-19.
Topics: Antiviral Agents; COVID-19; Humans; Hydroxychloroquine; Lopinavir; SARS-CoV-2; Treatment Outcome
PubMed: 33962524
DOI: 10.1080/17476348.2021.1927719 -
Frontiers in Immunology 2023After recognition of cognate antigen (Ag), effector CD8 T cells secrete serine proteases called granzymes in conjunction with perforin, allowing granzymes to enter and...
After recognition of cognate antigen (Ag), effector CD8 T cells secrete serine proteases called granzymes in conjunction with perforin, allowing granzymes to enter and kill target cells. While the roles for some granzymes during antiviral immune responses are well characterized, the function of others, such as granzyme C and its human ortholog granzyme H, is still unclear. Granzyme C is constitutively expressed by mature, cytolytic innate lymphoid 1 cells (ILC1s). Whether other antiviral effector cells also produce granzyme C and whether it is continually expressed or responsive to the environment is unknown. To explore this, we analyzed granzyme C expression in different murine skin-resident antiviral lymphocytes. At steady-state, dendritic epidermal T cells (DETCs) expressed granzyme C while dermal γδ T cells did not. CD8 tissue-resident memory T cells (T) generated in response to cutaneous viral infection with the poxvirus vaccinia virus (VACV) also expressed granzyme C. Both DETCs and virus-specific CD8 T upregulated granzyme C upon local VACV infection. Continual Ag exposure was not required for maintained T expression of granzyme C, although re-encounter with cognate Ag boosted expression. Additionally, IL-15 treatment increased granzyme C expression in both DETCs and T. Together, our data demonstrate that granzyme C is widely expressed by antiviral T cells in the skin and that expression is responsive to both environmental stimuli and TCR engagement. These data suggest that granzyme C may have functions other than killing in tissue-resident lymphocytes.
Topics: Mice; Humans; Animals; Granzymes; CD8-Positive T-Lymphocytes; Antiviral Agents; Immunity, Innate; Lymphocytes; Antigens; Vaccinia virus
PubMed: 37809077
DOI: 10.3389/fimmu.2023.1236595 -
Emerging Microbes & Infections Jan 2016Hepatitis C virus (HCV) infection affects approximately 3% of the world's population and causes chronic liver diseases, including liver fibrosis, cirrhosis, and... (Review)
Review
Hepatitis C virus (HCV) infection affects approximately 3% of the world's population and causes chronic liver diseases, including liver fibrosis, cirrhosis, and hepatocellular carcinoma. Although current antiviral therapy comprising direct-acting antivirals (DAAs) can achieve a quite satisfying sustained virological response (SVR) rate, it is still limited by viral resistance, long treatment duration, combined adverse reactions, and high costs. Moreover, the currently marketed antivirals fail to prevent graft reinfections in HCV patients who receive liver transplantations, probably due to the cell-to-cell transmission of the virus, which is also one of the main reasons behind treatment failure. HCV entry is a highly orchestrated process involving initial attachment and binding, post-binding interactions with host cell factors, internalization, and fusion between the virion and the host cell membrane. Together, these processes provide multiple novel and promising targets for antiviral therapy. Most entry inhibitors target host cell components with high genetic barriers and eliminate viral infection from the very beginning of the viral life cycle. In future, the addition of entry inhibitors to a combination of treatment regimens might optimize and widen the prevention and treatment of HCV infection. This review summarizes the molecular mechanisms and prospects of the current preclinical and clinical development of antiviral agents targeting HCV entry.
Topics: Antiviral Agents; Drug Discovery; Drug Therapy, Combination; Hepacivirus; Hepatitis C; Hepatitis C, Chronic; Hepatocytes; Humans; Interferon-alpha; Liver Neoplasms; Liver Transplantation; Virus Internalization
PubMed: 26733381
DOI: 10.1038/emi.2016.3 -
Viruses May 2022Immune homeostasis is achieved by balancing the activating and inhibitory signal transduction pathways mediated via cell surface receptors. Activation allows the host to... (Review)
Review
Immune homeostasis is achieved by balancing the activating and inhibitory signal transduction pathways mediated via cell surface receptors. Activation allows the host to mount an immune response to endogenous and exogenous antigens; suppressive modulation via inhibitory signaling protects the host from excessive inflammatory damage. The checkpoint regulation of myeloid cells during immune homeostasis raised their profile as important cellular targets for treating allergy, cancer and infectious disease. This review focuses on the structure and signaling of inhibitory receptors on myeloid cells, with particular attention placed on how the interplay between viruses and these receptors regulates antiviral immunity. The status of targeting inhibitory receptors on myeloid cells as a new therapeutic approach for antiviral treatment will be analyzed.
Topics: Antiviral Agents; Humans; Myeloid Cells; Neoplasms; Signal Transduction
PubMed: 35746616
DOI: 10.3390/v14061144 -
Biomolecules Oct 2019Throughout history, medicinal purposes of plants have been studied, documented, and acknowledged as an integral part of human healthcare systems. The development of... (Review)
Review
Throughout history, medicinal purposes of plants have been studied, documented, and acknowledged as an integral part of human healthcare systems. The development of modern medicine still relies largely on this historical knowledge of the use and preparation of plants and their extracts. Further research into the human microbiome highlights the interaction between immunomodulatory responses and plant-derived, prebiotic compounds. One such group of compounds includes the inulin-type fructans (ITFs), which may also act as signaling molecules and antioxidants. These multifunctional compounds occur in a small proportion of plants, many of which have recognized medicinal properties. is a well-known medicinal plant and products derived from it are sold globally for its cold- and flu-preventative and general health-promoting properties. Despite the well-documented phytochemical profile of plants and products, little research has looked into the possible role of ITFs in these products. This review aims to highlight the occurrence of ITFs in derived formulations and the potential role they play in immunomodulation.
Topics: Antioxidants; Antiviral Agents; Echinacea; Fructans; Immune System; Immunomodulation; Plant Extracts; Viruses
PubMed: 31623122
DOI: 10.3390/biom9100615 -
Nanotheranostics 2022Viral infection is a globally leading health issue. Annually, new lethal RNA viruses unexpectedly emerged and mutated threatening health and safety. Meanwhile, it is... (Review)
Review
Viral infection is a globally leading health issue. Annually, new lethal RNA viruses unexpectedly emerged and mutated threatening health and safety. Meanwhile, it is urgent to explore novel antiviral agents, which, however, takes years to be clinically available. Nonetheless, the development of carbon dots (CDs) in the past 20 years has exhibited their vast application potentials and revealed their promising capacity as future antiviral agents considering their versatile properties and significant antiviral responses. Thus, CDs have been widely investigated as an alternative of traditional chemotherapy for inhibiting viral infection and replication . Meanwhile, attempts to apply CDs to systems are in high demand. In this review, recent developments of CDs-based antiviral therapies are systematically summarized. Furthermore, the role of CDs in photodynamic inactivation to kill viruses or bacteria is briefly discussed.
Topics: Antiviral Agents; Carbon; Humans; Quantum Dots; RNA Virus Infections; Virus Diseases
PubMed: 36051856
DOI: 10.7150/ntno.73918 -
Trends in Immunology Jan 2021The majority of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals remain paucisymptomatic, contrasting with a minority of infected... (Review)
Review
The majority of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected individuals remain paucisymptomatic, contrasting with a minority of infected individuals in danger of death. Here, we speculate that the robust disease resistance of most individuals is due to a swift production of type I interferon (IFNα/β), presumably sufficient to lower the viremia. A minority of infected individuals with a preexisting chronic inflammatory state fail to mount this early efficient response, leading to a delayed harmful inflammatory response. To improve the epidemiological scenario, we propose combining: (i) the development of efficient antivirals administered early enough to assist in the production of endogenous IFNα/β; (ii) potentiating early IFN responses; (iii) administering anti-inflammatory treatments when needed, but not too early to interfere with endogenous antiviral responses.
Topics: Angiotensin-Converting Enzyme 2; Antiviral Agents; COVID-19; Cytokines; Humans; Immunologic Factors; Interferon Type I; SARS-CoV-2; Serine Endopeptidases; Virus Replication; COVID-19 Drug Treatment
PubMed: 33281063
DOI: 10.1016/j.it.2020.11.003